Ink jet recovery system having variable recovery

ABSTRACT

An ink jet recording apparatus comprising recovery means for maintaining and recovering the performance of discharge from a plurality of discharge ports for discharging a plurality of different inks for the recording, and control means for controlling such that the content of recovery by said recovery means for the discharge ports for discharging the ink not used for the subsequent recording, and the content of recovery by said recovery means for the discharge ports for discharging the ink used for the subsequent recording may be different.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an ink jet recovery apparatuswhich performs the recording by discharging the ink and a recoverymethod thereof, and more particularly to an ink jet recording apparatusfor use as a recording system for e.g. printers, copying machines,facsimiles, word processors, electronic typewriters, computers, as wellas a recovery method thereof.

[0003] 2. Related Background Art

[0004] Conventionally, the ink jet recording apparatuses performs therecording on the recording medium by discharging ink droplets throughthe discharge ports provided within an ink jet recording head, with theink supplied from an ink tank of e.g. cartridge type which is filledwith the ink for recording to the ink jet recording head.

[0005] Such an ink jet recording apparatus has the foreign matter suchas dust or bubble mixed into an ink supply system leading from an inktank to an ink jet recording head. Since the discharge ports provided onthe ink jet recording head or liquid channels in communication theretoare as small as about tens microns in inner diameter, the foreign mattersuch as dust or bubble, if reaching to any liquid channels, will adhereto the inner walls of liquid channels to impede the flow of ink,resulting in lower discharge efficiency of ink or reduced ink dischargeresponsibility to the recording signal, and in some extreme cases,clogging in discharge ports which may cause a discharge failureincluding ink non-discharge. Also, when the ink is not discharged for along time while the ink remains filled in the liquid channels of the inkjet recording head, the ink constituents will be thickened, and fixedtherein, resulting in a discharge failure of the ink.

[0006] Also, in the ink jet recording apparatus, if the foreign mattersuch as ink droplet, water droplet or dust is attached on the inkdischarge port face of the ink jet recording head, the ink droplet to bedischarged may be pulled by such adhering matter, resulting in deflecteddischarge direction or degraded image quality.

[0007] Thus, to resolve those inconveniences caused by the use of theink, the ink jet recording apparatus is provided with a specificconstitution which are not seen in other recording apparatuses, that is,a recovery system from discharge failure including means for cleaningaway the ink within the liquid channels, or making the discharge portface in good conditions.

[0008] One of the recovery methods from discharge failure with therecovery system is a method for leading the new ink into the liquidchannels, for example, a method of driving the discharge energygenerating elements to enable discharging of the ink not directlyinvolved in the recording to a predetermined ink acceptor (referred toas a “predischarge” or “idle discharge”). Also, there is a method ofcompulsorily expelling the ink through the discharge ports by exerting apredetermined pressure on the liquid channels, for example, bypressurizing an ink supply system, or sucking the ink through the inkdischarge ports (referred to as a “pumping”).

[0009] In addition, one of the methods of cleaning the discharge faceand preventing deflection in the ink discharge direction is a method ofhaving a wiping member for rubbing against the discharge port face towipe the foreign matter such as ink droplet or dust adhering near thedischarge ports by the relative movement of both (referred to as a“wiping”).

[0010] Because the recovery operation with the recovery system as abovedescribed increases the ink consumption for other than the recording, inthe conventional ink jet recording apparatuses, there have been proposedseveral methods, to reduce the waste of ink consumption for other thanthe recording, in which a plurality of carriages with recording headsmounted thereon are provided, and driven under control individually sothat the recording heads mounted on the carriages not involved in therecording are not subjected to recovery operation, as described inJapanese Laid-Open Patent Application No. 1-221251, or the occurrence ofdischarge failure is detected, and the recovery operation is performedbased on its-detected result, as described in Japanese Laid-Open PatentApplication No. 2-122935, or when a recovery switch is turned on, therecovery operation is performed in accordance with the history from theprevious recovery operation, as described in Japanese Laid-Open PatentApplication No. 4-250067.

[0011] However, the ink jet recording apparatus had a problem that whena plurality of carriages with recording heads mounted thereon areprovided as in the above conventional example, a plurality of recoverysystems corresponding to the carriages are required, resulting inincreased costs, and the lower recording speed for the switchingoperation of the carriages.

[0012] Furthermore, when the recovery operation is performed, based onthe result of detection of the discharge, or in accordance with thehistory following the previous recovery operation, the predischarge andwiping during the recording are effected for all the discharge ports ofthe recording heads, resulting in a problem of having increased inkconsumption for the recovery operation of discharging the ink notinvolved in the recording.

SUMMARY OF THE INVENTION

[0013] An object of the present invention is to resolve theaforementioned problems and to provide and propose an ink jet recordingapparatus, and a recovery method thereof, which performs the recordingusing a plurality of inks, wherein the recording is excellently effectedat all times without wastefully increasing the ink consumption for therecovery operation thereof.

[0014] It is another object of the invention to provide an ink jetrecording apparatus characterized by comprising recovery means formaintaining and recovering the performance of discharge from a pluralityof discharge ports for discharging a plurality of different inks for therecording, and control means for controlling such that the content ofrecovery by said recovery means for the discharge ports for dischargingthe ink not used for the subsequent recording and the content ofrecovery by said recovery means for the discharge ports for dischargingthe ink used for the subsequent recording may be different.

[0015] It is another object of the invention to provide a recoverymethod for an ink jet recording apparatus, characterized by including adetection process of detecting whether or not a plurality of differentinks will be used for the subsequent recording, and a recovery processof providing the recovery such that the content of recovery for aplurality of discharge ports for discharging each of said plurality ofinks for the recording may be different for each of said plurality ofinks, in accordance with the result of detection in said detectionprocess.

[0016] An ink jet recording apparatus of the present invention with arecording method thereof to resolve the aforementioned problemscomprises discriminating means for discriminating the ink involved inthe recording, an ink cartridge, or a recording head, and control meansfor providing recovery operation for the prevention or recovery ofnon-discharge of the ink from the discharge ports for discharging theink, based on the result of said discriminating means, characterized byproviding control such that the ink consumption of the recoveryoperation for the ink, the ink cartridge or the recording head involvedin the recording is lower than that of the recovery operation for theink, the ink cartridge or the recording head not involved in therecording. Thereby, it is possible to prevent unnecessary recoveryoperation or wasteful ink consumption, and effect the excellentrecording.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a perspective view illustrating the constitution of anink jet recording apparatus according to a first example of the presentinvention.

[0018]FIG. 2, composed of FIGS. 2A and 2B, is a block diagram showingthe configuration of a control circuit for the ink jet recordingapparatus according to the first example of the present invention.

[0019]FIG. 3 is a flowchart showing the procedure of a main control forthe ink jet recording apparatus according to the first example of thepresent invention.

[0020]FIG. 4 is a flowchart showing the detailed procedure of an initialprocess as shown in FIG. 3.

[0021]FIG. 5 is a flowchart showing the detailed procedure of a recoverycheck as shown in FIG. 3.

[0022]FIG. 6 is a flowchart showing the detailed procedure of a keyswitch check as shown in FIG. 3.

[0023]FIG. 7 is a flowchart further showing the detailed procedure of arecovery switch process as shown in FIG. 6.

[0024]FIG. 8 is a flowchart further showing the detailed procedure of arecording recovery switch process as shown in FIG. 7.

[0025]FIG. 9 is a flowchart further showing the detailed procedure of anon-recording recovery switch process as shown in FIG. 7.

[0026]FIG. 10 is a flowchart showing the detailed procedure of areceived data process as shown in FIG. 3.

[0027]FIG. 11 is a flowchart further showing the detailed procedure of arecording data process as shown in FIG. 10.

[0028]FIG. 12 is a flowchart showing the detailed procedure of arecovery operation before page recording as shown in FIG. 11.

[0029]FIG. 13 is a flowchart showing the detailed procedure of arecovery operation during page recording as shown in FIG. 11.

[0030]FIG. 14 is a flowchart further showing the detailed procedure ofan LF process as shown in FIG. 10.

[0031]FIG. 15 is a flowchart further showing the detailed procedure of arecovery operation after page recording as shown in FIG. 14.

[0032]FIG. 16 is a flowchart further showing the detailed procedure ofan FF process as shown in FIG. 10.

[0033]FIG. 17 is a perspective view illustrating the constitution of arecording head ink cartridge according to a second example of thepresent invention.

[0034]FIG. 18 is a perspective view illustrating the constitution of arecording head ink cartridge according to the second example of thepresent invention.

[0035]FIG. 19 is a perspective view illustrating the constitution of arecording head ink cartridge according to the second example of thepresent invention.

[0036]FIG. 20 is a flowchart showing the procedure of a controloperation according to a third example of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] The embodiments of the present invention will be now describedparticularly and specifically with reference to the drawings.

FIRST EXAMPLE

[0038]FIG. 1 illustrates the constitution of an ink jet recordingapparatus to which the present invention is applied. Herein, 1B is a BKrecording head for the recording by discharging the black (BK) ink. 1Y,1M, 1C are a Y recording head, an M recording head, and a C recordinghead for the recording by discharging the color inks of yellow (Y),magenta (M) and cyan (C), respectively. In this example, each of therecording heads has electricity-heat converters for generating the heatenergy for use in discharging the ink provided corresponding todischarge ports. Also, 2B, 2Y, 2M and 2C are ink cartridges forsupplying respective color inks to the BK recording head 1B, the Yrecording head 1Y, the M recording head 1M and the C recording head 1C,respectively, wherein the recording heads 1B, 1Y, 1M, 1C and the inkcartridges 2B, 2Y, 2M, 2C which are connected together are mounted on acarriage 3. 4 and 5 are a guide shaft and a guide rail, respectively,for guiding the movement of the carriage 3, 6 is a timing belt connectedto the carriage 3 and stretched between a drive pulley 7 and an idlepulley 8, and 9 is a carriage driving motor for moving the carriage 3for the scan via the timing belt.

[0039]10 is a recording medium (recording sheet), 11 and 12 are a sheetfeed roller and a pinch roller for feeding the recording sheet 10therebetween to the recording position, and 13 is a sheet exhaust rollerfor exhausting the recording sheet 10 which has been recorded. Note thatthe recording is performed by discharging the inks in accordance withthe recording signals from the recording heads 1BK to 1C during onescanning of movement by the carriage 3, whereby the recording sheet 10is fed by a sheet feed motor, not shown (as shown at 14 in FIG. 2B) atevery recording of one scan.

[0040]15BK, 15Y, 15M, and 15C are cap members placed at positionsopposite the ink discharge port faces of recording heads 1BK, 1Y, 1M, 1Coutside the recording area, 16 is a wiping member, 17 is a suction pumpfor the suction operation for maintaining the ink discharge functionfrom each of the recording heads 1BK to 1C, with the ink discharge portface capped with each of the cap members 15BK, 15Y, 15M, 15C, and 18 isa recovery system motor engaged in a series of recovery operationsincluding the suction operation. Note that the cap members 15BK to 15Cand the wiping member 16 are operated by the motor 18 via a drivingmechanism not shown, so that the cap members 15BK to 15C can beforcefully advanced or retracted for the capping, while the wipingmember 16 is subjected to the wiping operation by movement of thecarriage 3 once led to a position for wiping the ink discharge portface.

[0041] That is, the cap members 15BK to 15C, the wiping member 16 andthe suction pump 17 are connected via the driving mechanism to therecovery system motor 18, wherein the cap members 15BK, 15Y, 15M, 15Cand the wiping member 16 are advanced or retracted to or from therecording heads 1BK, 1Y, 1M, 1C, when driven in rotation by the recoverysystem motor 18, thereby effecting suction with the pump 17.Accordingly, the wiping and suction operation can be made for any of therecording heads 1BK, 1Y, 1M, 1C by controlling the carriage drivingmotor 9 and the recovery system motor 18.

[0042] In the vicinity of the cap members 15BK, 15Y, 15M, 15C isprovided a predischarge receiver (not shown), with which thepredischarge can be effected by driving the recording heads 1BK, 1Y, 1M,1C to discharge the ink through all ink discharge ports after havingmoved the recording heads 1BK, 1H, 1M, 1C to the position opposite thepredischarge receiver. Also, a carriage position detecting sensor 19(see FIG. 2B) for detecting the position of the carriage 3 is providedin a movement range of the carriage 3. Also, a sheet detecting sensor 20for detecting the presence or absence of the recording sheet 10 or itsedge is provided on the course of conveying the recording sheet 10.

[0043]FIGS. 2A and 2B show the configuration of a control circuit for anink jet recording apparatus of the present invention. In the samefigure, 201 is a CPU, e.g. in the form of a microcomputer for performingvarious controls in accordance with the set procedure involving therecording, 202 is a RAM having an area for expanding the text data orimage data, a storage area of various parameters, and a work area, 203is a ROM for storing the programs corresponding to the above-mentionedprocedures and fixed data such as font data, and 204 is a timer forproducing the execution cycle or the timing necessary for the recordingoperation.

[0044] Also, 205BK is a detection unit for detecting the use of the BKrecording head 1BK and its temperature, or whether the ink remainswithin the BK ink cartridge 2BK, 206BK is a BK line buffer for storingrecord data for the BK recording head 1BK, 207BK is a BK head driver fordelivering a recording signal or electric power to the BK recording head1BK, and 208BK is a BK dot counter for counting effective dots for therecording in the record data transferred to the BK line buffer 206BK.

[0045] In a similar way, for the recording heads 1Y, 1M and 11C, thereare also provided a Y detection unit 205Y, a Y line buffer 206Y, a Yhead driver 207Y, and a Y effective dot counter 208Y; an M detectionunit 205M, an M line buffer 206M, an M head driver 207M, and an Meffective dot counter 208M; and a C detection unit 205C, a C line buffer206C, a C head driver 207C, and a C effective counter 208C.

[0046] Also, 209A, 209B, and 209C are motor drivers for delivering asignal or electric power required to drive the carriage driving motor 9,the sheet feeding motor 14, and the recovery system motor 18,respectively. Further, 210 is an external memory device such as a fontcard, 211 is an external interface for the communication with a hostcomputer, not shown, 212 is a key switch for enabling various settingsor operations, and 213 is a display unit for displaying the error or setstate of the apparatus. Note that a power supply which is not containedin FIGS. 2A and 2B are further provided to supply the electric power tothe above electrical circuit.

[0047] With the above circuit configuration, the recording can beperformed on the recording sheet 10 by a printing mechanism of the inkjet recording apparatus, and its control sequence will be outlined belowin accordance with the flowcharts of FIG. 3 and following figures.

[0048]FIG. 3 shows a main control of the ink jet recording apparatusaccording to the present invention. First, upon turning on the electricpower, various initializations are performed at step S301. Then, at stepS302, an error check is performed, and at step S303, a recovery check isperformed. Subsequently, at S304, a key switch check is performed, andat step S305, a received data processing is carried out. And then theprocedure returns to step S302, to repeat the operations from step S302to step S305.

[0049]FIG. 4 is a flowchart showing the details of the initialprocessing at step S301 as shown in FIG. 3. That is, as the detailedprocedure of the initial processing S301, a check for ROM 203 and RAM202 is made at step S401. That is, it is checked whether or not theprogram or data stored is normally operable. Then at step S402, variousparameters are initialized. That is, every time the power supply isturned on, necessary parameters are set at predetermined values. Notethat in the initialization of parameters, a flag for no color for use incurrent recording is set. Then at step S403, the input/output for theapparatus is initialized. Specifically, the display unit 213 and theexternal interface 211 are initialized. And at step S404, the mechanismfor the ink jet recording apparatus is initialized. Specifically, afterthe initialization of ICs within the recording head 1 (1BK to 1C) andthe phasing of motors, the recovery system motor 18 is driven to bringthe cap members 15 (15BK to 15C) into a retracted position from therecording head 1, the carriage driving motor 9 is driven to detectswitching of the carriage position detecting sensor 19 to find theposition of the carriage 3, and after moving the recording head 1 to theposition opposite the cap members 15, the recovery system motor 18 isdriven to perform the capping for the recording head 1. Also, if anyunnecessary recording sheet 10 is detected by the sheet detecting sensor20, the recording sheet 10 is exhausted by driving the sheet feedingmotor 14. In this way, this procedure is completed with the initialprocessing at step S404.

[0050]FIG. 5 shows the detailed procedure of the recovery check at stepS303 involving the main control of the present invention as shown inFIG. 3. As the procedure for the recovery check at step S303, first atstep S501, the open accumulation time for the cap members 15 is checked.Specifically, a determination is made whether or not the accumulationtime of the recording head 1 while in a cap open state measured by thetimer 204 as shown in FIGS. 2A and 2B are equal to or greater than apredetermined value Topen. This is required due to the fact that the inkdischarge state of the recording head 1 is different between the capopen and closed states, wherein the ink discharge unit is opened in thecap open state, having a greater amount of ink evaporable componentsevaporating from the discharge ports, with more possibility that thedust sticks thereto, requiring the recovery operation at shorterintervals, than in the cap closed state. And if the result ofdetermination at step S501 is affirmative, the procedure proceeds tostep S502, where a determination is made whether or not the elapsed timefrom the previous pumping operation by the pump 17 for the recordinghead 1 is equal to or greater than a predetermined value Tpo.

[0051] Normally, the recording head 1 is devised to be capped or heatretained within the cap when not in use to suppress evaporation of theink through the discharge ports, or prevent the discharge ports fromdrying through the periodical predischarges, but when left away for thevery long time, the ink within the ink flow passageways leading from theink cartridges 2 (2BK to 2C) to the recording head 1 will evaporatethrough the wall faces, producing more air bubbles within the ink flowpassageways, possibly resulting in a discharge failure. Note that torecover from the discharge failure, it is effective to compulsorily suck(pump) the ink through the discharge ports of the recording head 1.Thus, if the result of determination at step S502 is affirmative, thepumping is determined to be required, the procedure proceeds to stepS503, where the pumping by a predetermined amount of ink Mpo and thepredischarge by a predetermined amount of ink Npo are performed, andthen the wiping is carried out, and is ended.

[0052] Also, if the result of determination at step S502 is negative,the procedure proceeds to step S504 to determine whether or not theelapsed time from the previous predischarge is equal to or greater thana predetermined value Tyo. If the recording head 1 is not used for thelong time, the viscosity of the ink near the discharge ports rises dueto evaporation of the ink through the discharge ports of the recordinghead 1, causing a discharge failure. And in such cases, to recover fromthe discharge failure, the predischarge from the recording head 1 can beeffectively performed. Thus, if the result of determination at step S504is affirmative, the predischarge is determined to be required, and theprocedure proceeds to step S505. At step S505, the predischarge by apredetermined amount of ink Nyo is performed, and then at step S506, theopen cap accumulation time is cleared. Also, if the result ofdetermination at step S504 is negative, the steps S505, S506 arebypassed, and the procedure proceeds directly to step S507. Thus, atstep S507, a determination is made whether or not the elapsed time fromthe previous wiping is equal to or greater than a predetermined valueTwo.

[0053] Due to the ink discharge from the recording head 1 and themovement of the recording head 1 relative to the recording sheet 10, theink mist, paper powder or dust may adhere onto the ink discharge face ofthe recording head 1, causing a discharge failure or deviated dischargedirection. In such cases, to recover from the discharge failure ordeviated discharge direction, the wiping of the recording head 1 iseffective. Thus, if the result of determination at step S507 isaffirmative, the wiping is determined to be required. And at step S508,the wiping is executed, and then the procedure is ended. Note that ifthe result of determination at step S507 is negative, the step S508 isbypassed, and the procedure is ended.

[0054] Also, if the result of determination at step S501 is negative,the procedure proceeds to step S509 to determine whether or not theelapsed time from the previous pumping by the pump 17 for the recordinghead 1 is equal to or greater than a predetermined value Tpc. If theresult of determination at step S509 is affirmative, the pumping isdetermined to be required. And at step S510, the pumping by apredetermined amount of ink Mpc and the predischarge by a predeterminedamount of ink Npc are performed, then the wiping is executed, and theprocedure is ended. If the result of determination at step S509 isnegative, the procedure proceeds to step S511 to determine whether ornot the elapsed time from the previous predischarge is equal to orgreater than a predetermined value Tyc.

[0055] If the result of determination at step S511 is affirmative, thepredischarge is determined to be required, and the procedure proceeds tostep S512 to effect predischarge by a predetermined amount of ink Nyc,and then the procedure proceeds to step S513. Also, if the result ofdetermination at step S511 is negative, the step S512 is bypassed, andthe procedure proceeds to step S513 to determine whether or not theelapsed time from the previous wiping is equal to or greater than apredetermined value Twc. If the result of determination at step S513 isaffirmative, the wiping is determined to be required, and the procedureproceeds to step S514 to effect wiping, and is ended. Also, if theresult of determination at step S513 is negative, the step S514 isbypassed, and the procedure is ended.

[0056] Note that for the recovery check S303 as above described, thedistinction between ink colors is not made for the simplicity ofexplanation, but the recovery check procedure is performed separatelyfor each ink color, that is, the recovery operation comprised ofpumping, predischarge, and wiping are determined and performed undercontrol independent for each of the recording heads 1BK, 1Y, 1M, 1C.Thus, for the recovery check S303, the optimal recovery operation can beeffected in accordance with the history of each recording head 1.

[0057]FIG. 6 shows the detailed procedure of key switch check at stepS304 as shown in FIG. 3. For the key switch check S304, a determinationis first made at step S601 whether or not a recovery switch is operated.If the result of determination at step S601 is affirmative, theprocedure proceeds to step S602 for the recovery switch process, andthen is ended. Also, if the result of determination at step S601 isnegative, the procedure proceeds to step S603 to determine whether ornot an ink exchange switch is operated. If the result of determinationat step S603 is affirmative, the procedure proceeds to step S604 for theprocess for ink exchange, or specifically, to move the carriage 3 to anexchange position to check for an exchange of the ink cartridge 2, andperform the recovery operation for a new ink cartridge after the inkcartridge is exchanged, i.e., the pumping and predischarge by anadequate amount of ink, and the wiping, and the procedure is ended.

[0058] Also, if the result of determination at step S603 is negative,the procedure proceeds to step S605 to determine whether or not therecording head exchange switch is operated. If the result ofdetermination at step S606 is affirmative, the procedure proceeds tostep S606 for the recording head exchange process, or specifically, tomove the carriage 3 to the exchange position, check for an exchange ofthe recording head 1, and perform the recovery operation for a newrecording head 1 after the recording head is mounted, i.e., the pumpingand predischage by an adequate amount of ink, and the wiping, and theprocedure is ended.

[0059] Also, if the result of determination at step S605 is negative,the procedure proceeds to step S607 to determine whether or not otherswitches are operated. If the result of determination at step S607 isaffirmative, the procedure proceeds to step S608 to perform a processfor other switches, or specifically, make setting of recordingparameters, feed and supply of the recording sheet, line feed, exhaust,and interruption of recording, and is ended.

[0060] While in the key switch check S304, the process corresponding tothe key switch 212 was involved, it is needless to say that when thecommand is input from the external interface 211 or the informationdevice is integrally provided, the similar process can be also performedupon an input from the display unit 213.

[0061]FIG. 7 further shows the detailed procedure of recovery switchprocess according to the present invention at step S602 as shown in FIG.6. That is, for the step S602 for recovery switch process, adetermination is first made at step S701 whether or not there remainsthe ink being currently used for recording. And if the result ofdetermination at step S701 is affirmative, it is determined that thereoccurs the inconvenience in discharging the ink being used, and theprocedure proceeds to step S702 to effect a recording recovery switchprocess for the recording head discharging the ink, and is ended. Also,if the result of determination at step S701 is negative, the procedureproceeds to step S703 to effect a non-recording recovery switch processfor the recording head 1, and then is ended.

[0062] Referring to FIG. 8, the detailed procedure of the recordingrecovery switch process at step S702 as shown in FIG. 7 is described.

[0063] First, it is detected at step S801 whether or not there occurs adischarge failure for the ink being currently used for the recording.Specific means for detecting the discharge failure may be any well-knownmeans. As an example, means for detecting the flying ink dropletdischarged from each of discharge ports may be conceived. Note thatunless any non-discharge is detected, this process is ended. Also, ifany non-discharge is detected, the procedure proceeds to the next stepS802 to pump the non-discharged ink which has been determined as thedischarge failure as a result of detection at step S801. Then, theprocedure proceeds to step S803 to predischarge the ink being used forthe recording, and to step S804 to wipe the recording head 1 used forthe recording, and then the procedure is ended. Note that this procedureis performed for all the recording heads 1 being used in discharging theink.

[0064] Owing to such recording recovery switch process S702, therecovery operation from the non-discharge which has occurred duringrecording can be securely effected without consuming wastefully the inknot involved in the recording upon the recovery operation.

[0065]FIG. 9 shows the detailed procedure of the non-recording recoveryswitch process at step S703 as shown in FIG. 7.

[0066] In the procedure for the non-recording recovery switch processS703, first at step S901, the non-discharge for all the recording heads1BK to 1C is detected. Herein, if it is determined that thenon-discharge for all the recording heads 1BK to 1C does not exist, thisprocedure is ended. Also, if the result is affirmative, the procedureproceeds to the next step S902 to effect pumping of the recording headwhich has been determined as the non-discharge as a result of detectionat step S901. Then at step S903, the predischarge for all the recordingheads 1BK to 1C is performed. At step S904, the wiping for all therecording heads 1 is performed, and the procedure is ended.

[0067]FIG. 10 shows the detailed procedure of received data process atstep S305 as shown in FIG. 3.

[0068] First, at step S1001, a determination is made whether or notthere is received data from the external interface 211. If the result ofdetermination at step S1001 is affirmative, that is, no received data,this processing is ended. If the result of determination at step S1001is negative, that is, received data present, the procedure proceeds tostep S1002 to determine whether or not the received data is a commandfor setting the color for use in recording. If the result ofdetermination at step S1002 is affirmative, the procedure proceeds tostep S100 to set (store) the color for use in recording, and is ended.Also, if the result of determination at step S1002 is negative, theprocedure proceeds to step S1004 to determine whether or not receiveddata is recording data. And if the result of determination at step S1004is affirmative, the procedure proceeds to step S1005 to process therecording data, and is ended. Specifically, the recording data istransferred to the line buffers 206BK, 206Y, 206M, 206C corresponding tothe recording colors.

[0069] Also, if the result of determination at step S1004 is negative,the procedure proceeds to step S1006 to determine whether or not thereceived data is a CR command (code). If the result of determination atstep S1006 is affirmative, the procedure proceeds to step S1007 toprocess recording data in accordance with its command, and is ended.Also, if the result of determination at step S1006 is negative, theprocedure proceeds to step S1008 to determine whether or not receiveddata is an LF command (code). And if the result of determination at stepS1008 is affirmative, the procedure proceeds to step S1009 to execute LFprocessing, and is ended. Also, if the result of determination at stepS1008 is negative, the procedure proceeds to step S1010 to determinewhether or not the received data is an FF command (code). And if theresult of determination at step S1010 is affirmative, the procedureproceeds to step S1011 to execute FF processing, and is ended. Also, ifthe result of determination at step S1010 is negative, the procedureproceeds to step S1012 to process other received data, and is ended.

[0070]FIG. 11 shows the detailed procedure of recording data process atstep S1005 as shown in FIG. 10. As the procedure of the recording dataprocess S1005, first at step S1101, a determination is made whether ornot the sheet has been fed and supplied. If the result of determinationat step S1101 is negative, or the sheet has not been fed and supplied,the procedure proceeds to step S1102 to feed and supply the sheet. Inthis example, automatic feed and supply means is omitted, but the feedand supply can be effected by well-known techniques. At step S1103, therecovery processing before the start of page recording is executed, andthe procedure proceeds to step S1104, but if the result of determinationat step S1101 is affirmative, the procedure proceeds directly to stepS1104 by bypassing the steps S1102 and S1103. Thus, line recording isperformed at step S1104. Specifically, the recording data within theline buffer 206 is transferred to the recording head 1 to enable a headdriver 207 to perform the recording by discharging the ink from therecording head 1 onto the recording sheet 10, while the carriage drivemotor 9 is driven to move the carriage 3 along the guide shaft 12. Andat step S1105, the recovery process during page recording is executed atstep S1105, and the processing is ended.

[0071]FIG. 12 shows the detailed procedure of recovery process beforepage recording at step S1103 as shown in FIG. 11. This procedure firstopens the cap member 15 of the recording head 1 at step S1201. Note thatin this example, the cap member 15 is opened and sealed in a unit ofpage. Then, at step S1202, a determination is made whether or not therecording head discharges none of the ink being currently used forrecording. And if the answer is affirmative, or the non-discharge, theprocedure proceeds to step S1203 to pump the recording head 1 for theink which has been determined as the non-discharge as a result ofdetermination at step S1202. Then, at step S1204, the predischarge isperformed for the ink being used for recording. At step S1205, thewiping of the recording head 1 in use for recording is performed, andthe processing is ended.

[0072] Owing to such recovery process before page recording S1103, theink discharge before page recording can be retained in good conditionswithout consuming wastefully the ink not involved in recording upon therecovery operation.

[0073]FIG. 13 shows the detailed procedure of recovery process duringpage recording according to the present invention at step S1105 as shownin FIG. 11.

[0074] First, at step S1301, a determination is made whether or not theelapsed time from the previous predischarge of that ink is equal to orgreater than Typ, with an array of discharge ports of the recording head1 being currently used for recording. And if the result of determinationherein is affirmative, the procedure proceeds to step S1302 topredischarge the ink in use for recording by a predetermined amount ofink Nyp, and then to step S1303. Also, if the result of determination atstep S1301 is negative, the procedure bypasses step S1302 and proceedsto step S1303. At step S1303, a determination is made whether or not theelapsed time from the previous wiping for the recording head 1 used forrecording is equal to or greater than Twp. And if the result ofdetermination at step S1303 is affirmative, the procedure proceeds tostep S1304 to wipe the recording head 1 used for recording, and isended. Also, if the result of determination at step S1303 is negative,the procedure bypasses step S1304 and is ended.

[0075] Owing to such recovery process during page recording S1105, therecording head 1 during page recording for which the line recording isrepeated is allowed to excellently perform the recording withoutconsuming wastefully the ink not involved in recording upon the recoveryoperation, while preventing the occurrence of non-discharge due to inkevaporation from the discharge ports, or sticking of ink mist, paperpowder or dust onto the discharge port face.

[0076]FIG. 14 shows the detailed procedure of LF process at step S1009as shown in FIG. 10.

[0077] First, at step S1401, the recording sheet 10 is fed by apredetermined amount set by the command or with designation of therecording mode. And at step S1402, a determination is made whether ornot the line-renewal length of recording limit is exceeded. Theline-renewal length of recording limit can be obtained based on thelength of recording sheet 1 set by the command, or upon the detection ofthe bottom end of the recording sheet 10 by the sheet detection sheetsensor 20 provided in the ink jet recording apparatus. If the result ofdetermination at step S1402 is affirmative, the procedure proceeds tostep S1403 to exhaust the recording sheet 10. And the procedure proceedsto step S1404 to perform recovery operation after page recording, and tostep S1405 to set a flag indicating no color used for recording, andthen is ended. Note that if the result of determination at step S1402 isnegative, the processing is ended.

[0078]FIG. 15 shows the details of recovery operation processingprocedure after page recording according to the present invention atstep S1405 as shown in FIG. 14. For the recording operation after pagerecording S1405, first at step S1501, a determination is made whether ornot the elapsed time from the previous predischarge of ink is equal toor greater than Typ, with an array of ink discharge ports for therecording head 1 in current use for recording. And if the result ofdetermination is affirmative, the procedure proceeds to step S1502 topredischarge the ink used for recording by a predetermined amount Nyp,and to step S1503. Also, if the result of determination at step S1301 isnegative, the procedure bypasses step S1502 and proceeds to step S1503.At step S1503, the wiping of the recording head 1 used in recording isperformed, and the procedure proceeds to step S1504. And at step S1504,the recording head 1 is capped and the procedure is ended.

[0079] Owing to such recovery process after page recording S1405, it ispossible to remove the cause of discharge failure of the recording head1 due to evaporation of the ink from the discharge ports in the cap openstate, or sticking of ink mist, paper powder, or dust onto the dischargeport face, without consuming wastefully the ink not involved inrecording upon the recovery operation, and prevent the non-discharge dueto being left away for the long time in the capped state.

[0080]FIG. 16 shows the detailed procedure of FF process by an exhaustcommand at step S1011 as shown in FIG. 10. In the FF process S1011,first at step S1601, a determination is made whether or not the sheethas been fed and supplied. And if the result of determination isaffirmative, the procedure proceeds to step S1602 to exhaust therecording sheet 10. The steps following this step S1602 correspond tothose following the step S1403 of FIG. 14. That is, at the next stepS1603, the recovery operation after page recording is performed, and atstep S1604, a flag indicating no color used for recording is set up, andthe procedure is ended. Also, if the result of determination at stepS1601 is negative, the procedure proceeds to step S1605 to feed andsupply the recording sheet 10. Note that step S1605 corresponds to S1102of FIG. 11. Thus, at step S1606, the recovery operation before pagerecording is performed and the procedure is ended.

[0081] As above described, with this example, the recording can beexcellently effected without wastefully consuming the ink not involvedin the recording upon the recovery operation for the recording headduring the recording. Also for the ink not involved in recording, theexcellent recording condition can be retained by the periodical recoveryprocessing as shown in FIG. 5.

SECOND EXAMPLE

[0082]FIGS. 17, 18 and 19 illustrate the constitution of a recordinghead and an ink cartridge according to another example of the presentinvention.

[0083]FIG. 17 exemplifies one constitution in which a recording head1701 is commonly employed for BK, Y, M and C inks, with discharge portcolumns 101BK, 101Y, 101M and 101C separately provided. The inkcartridges 1702BK, 1702Y, 1702M and 1702C can be exchanged independentlyof one another. By having the recording head 1701 integrally formed inthis way, the recording head can be manufactured inexpensively. Also,where a cap member is commonly provided for all the ink discharge portsin the recording head 1701, the suction of the ink can not be madeindependently of other inks. Also, the wiping of the ink can not be madeindependently. However, the use of the recovery process of the presentinvention makes it possible to effect the excellent recording, with goodpreservation when out of service, without consuming wastefully the inknot involved in recording upon the recovery operation by predischargeduring recording.

[0084]FIG. 18 exemplifies another constitution in which a recording head1801 is commonly employed, with discharge port columns 101BK to 101Cseparately provided. Also, the ink tanks Y, M, C are incorporated intoan integral cartridge 1802YMC, and only a BK ink tank is made a separatecartridge 1802BK. Similarly, by constituting the recording head 1801 asone piece, the recording head can be manufactured cheaply. Also, when acap member is commonly provided for all the ink discharge ports in therecording head, the suction of the ink, as well as the wiping, can notbe made independently of other inks, but because the frequency of usingthe BK ink in the normal recording condition is higher than that ofusing YMC inks, the use of a head unit of this example makes it possibleto effect the excellent recording, with good preservation when out ofservice, without consuming wastefully the Y, M, C inks which haverelatively lower use frequency upon the recovery operation bypredischarge during recording with only the BK ink.

[0085] Also, when an integral cartridge for the BK, Y, M, C inks isprovided, it is possible to eliminate the waste produced in the recoveryoperation by predischarge during recording.

[0086]FIG. 19 exemplifies another constitution in which a BK inkrecording head 1901 and an YMC ink recording head 1902 are providedseparately. In this case, the cap members are individually provided forthe recording heads 1901, 1902 to allow for the individual suction.Accordingly, it is possible to effect the excellent recording, with goodpreservation when out of service, without consuming wastefully the Y, M,C inks having lower use frequency upon the recovery operation by suctionor predischarge during recording.

THIRD EXAMPLE

[0087] While in the first example, the ink for use within the page wasspecified before page recording by a command, it will be understood thatwhen an information processing device is integrated with the ink jetrecording apparatus, it is easy to check the recording data anddiscriminate the ink used for the recording. However, when the ink jetrecording apparatus is controlled by received data from the host side,the host side must check recording data, determine the ink actually usedfor the recording, and send a command indicating the use color to theink jet recording apparatus. When only the BK ink is used, the check forrecording data is simple, but the discrimination of the ink actuallyused from color recording data impose great burden on the host side,because of a large amount of recording data. FIG. 20 shows a controloperation procedure for analyzing the recording data in the ink jetrecording apparatus itself and discriminating the ink actually used forthe recording without specification by the command from the host side.In the case of normal color recording data, it is almost common thatafter the command for designating the color, recording data appears insuccession, to correspond to the recording data process as shown at stepS1005 in FIG. 10.

[0088] First, at step S2001, a color designating command for recordingdata is checked. When the designation at step S2001 is BK or none, theprocedure proceeds to step S2002. And at step S2002, recording data istransferred to a BK line buffer 206BK (see FIG. 2A). Then at step S2003,a determination is made whether or not recording data is blank (white).That is, as shown in FIG. 2A, an effective dot counter 208BK is providedin front of the BK line buffer 206BK and can count the effective numberof data from the recording data. Thus, it is determined that if thevalue of the effective dot counter 203BK is zero, the black ink is notused, while if it is one or greater, the black ink is used. If theresult of determination at step S2003 is negative, the procedureproceeds to step S2004 to add black to the recording colors to be used,and is ended. Also, if the result of determination at step S2003 isaffirmative, the procedure is directly ended. Thus, the similarprocessings are performed for the recording data color designationcommands for Y, M, and C.

[0089] That is, if the color designation is Y at step S2005, theprocedure from step S2006 to step S2008 is followed, while if the colordesignation is C at step S2009, the procedure from step S2101 to S2012is followed. If the determination is negative at step S2009, the colordesignation is supposed as M, and the processing is made following theprocedure from step S2013 to S2015.

[0090] Accordingly, without burden on the host side, the ink jetrecording apparatus can discriminate the ink to be used for therecording, and allows the excellent recording, with good preservationwhen out of service, without consuming wastefully the ink not involvedin recording upon the recovery operation by suction or predischargeduring recording.

[0091] While in the third example, recording data was provided insuccession after the color designation command, it will be appreciatedthat when recording data is received in dot sequence, the recording datamay be transferred to the line buffer for each color in units of dot,with the effective dot counter provided in front of the line buffer,whereby the ink used for the recording can be discriminated by checkingthe content of the effective dot counter, with the same effect obtained.

[0092] Also, while in the first example, the ink used for the recordingis discriminated in units of page, it will be appreciated that the inkused for the recording may be discriminated in units of job extendingover several pages.

[0093] When using a plurality of inks having different densities withthe same color tone, the same processing may be made with less wastefulconsumption of the ink, by discriminating the ink not to be used withthe designation of the recording mode.

[0094] Regarding the color information, the ink used for the recordingcan be discriminated for not only YMCK but also other descriptions suchas RGB, HSV, Lab, XYZ by checking the color used or not used in the YMCKin the process of transformation into YMCK information, with the sameeffect obtained.

[0095] According to the present invention, the excellent recording, withgood preservation when out of service, can be made without consumingwastefully the ink not involved in recording upon the recovery operationby ink suction or predischarge from the recording head used duringrecording.

[0096] Also, when the recording head or ink cartridge is not providedseparately for each ink color, the excellent recording, with goodpreservation when out of service, can be effected without consumingwastefully the ink upon the recovery operation by ink suction orpredischarge from the recording head used during recording.

[0097] Furthermore, the excellent recording, with good preservation whenout of service, can be made without consuming wastefully the ink uponthe recovery operation by ink suction or predischarge as abovementioned, without burden on the host information processing device.

What is claimed is:
 1. An ink jet recording apparatus characterized bycomprising: recovery means for maintaining and recovering theperformance of discharge from a plurality of discharge ports fordischarging a plurality of different inks for the recording; and controlmeans for controlling such that the content of recovery by said recoverymeans for the discharge ports for discharging the ink not used for thesubsequent recording, and the content of recovery by said recovery meansfor the discharge ports for discharging the ink used for the subsequentrecording may be different.
 2. An ink jet recording apparatus accordingto claim 1, wherein said control means controls such that the content ofrecovery by said recovery means for discharge ports for discharging theink not to be used for the subsequent recording is less in magnitudethan the content of recovery by said recovery means for discharge portsfor discharging the ink to be used for the subsequent recording.
 3. Anink jet recording apparatus according to claim 1, wherein said recoverymeans discharges the ink not involved in recording from said dischargeports.
 4. An ink jet recording apparatus according to claim 1, whereinsaid recovery means sucks the ink from said discharge ports.
 5. An inkjet recording apparatus according to claim 1, wherein said recoverymeans wipes said discharge ports.
 6. An ink jet recording apparatusaccording to claim 1, further comprising detecting means for detectingwhether or not a plurality of different inks will be used for thesubsequent recording.
 7. A recovery method for an ink jet recordingapparatus, characterized by including: a detection process of detectingwhether or not a plurality of different inks will be used for thesubsequent recording; and a recovery process of providing the recoverysuch that the content of recovery for a plurality of discharge ports fordischarging each of said plurality of inks for the recording may bedifferent for each of said plurality of inks, in accordance with theresult of detection in said detection process.
 8. A recovery method foran ink jet recording apparatus according to claim 7, wherein in saidrecovery process, the content of recovery by said recovery means fordischarge ports for discharging the ink not to be used for thesubsequent recording is less in magnitude than the content of recoveryby said recovery means for discharge ports for discharging the ink to beused for the subsequent recording.
 9. A recovery method for an ink jetrecording apparatus according to claim 7, further including dischargingthe ink not involved in recording from said discharge ports in saidrecovery process.
 10. A recovery method for an ink jet recordingapparatus according to claim 7, further including sucking the ink fromsaid discharge ports in said recovery process.
 11. A recovery method foran ink jet recording apparatus according to claim 7, further includingwiping said discharge ports in said recovery process.
 12. A recoverymethod for an ink jet recording apparatus according to claim 7, whereinthe heat energy is used to discharge the ink from said discharge ports.